1. Technical Field
The present invention relates to powder supply devices, and particularly to a powder supply device for supplying a powder, such as powder metal and the like, used for laser cladding processing, for example.
2. Background Art
Conventionally, laser processing is known whereby, e.g., in order to increase the durability of the valve seat of an engine cylinder head while increasing its design freedom, the valve seat is irradiated with laser while a powder (powdered) overlay material, for example, is supplied, forming an overlay layer (cladding layer) as the valve seat and the laser are relatively rotated. This laser processing is a technology where the cylinder head that has been subjected to machining processing required for an engine combustion chamber, such as valve opening forming processing, is irradiated with laser while the powdered overlay material including a copper alloy and the like and having abrasion resistance is supplied to an area where the valve seat is to be formed, forming a ring-shaped overlay layer, namely an overlay head portion, that is to eventually provide the valve seat. Generally, the technology is referred to as laser cladding processing.
The quality of the product subjected to the laser cladding processing depends on the amount of supply of the overlay material to the nozzle during the laser cladding processing. Thus, in the relevant field, there is a need for highly accurately adjusting the amount of supply of the overlay material (powder).
In order to address such need, Patent Document 1 discloses a powder supply device that is capable of continuous operation while highly accurately controlling the amount of supply of powder, and that increases the ease of use in various use environments.
The powder supply device disclosed in Patent Document 1 includes a powder supply means provided with a sub-hopper with capacity equal to or greater than the amount of supply required in a unit of processing step; a powder route to the powder supply means including a series of a main hopper and a powder replenishing means, the main hopper having capacity equal to or greater than the amount of supply required throughout the entire steps; and a control means that causes the powder supply means to operate based on the amount of powder held in the powder supply means, and that causes the powder replenishing means to operate in accordance with the amount of powder held in the powder supply means and a operation state thereof.